Thermostatically actuated control system



Feb. 21, 1950 w. B. ELMER 2,498,259

THERMOSTATICALLY ACTUATED CONTROL SYSTEM Filed Feb. 22, 1945 .2 Sheets-Sheet 1 WITNESS: INVENTOR BY M 6,1 ATTORNEY Feb. 21, 1950 w. B. ELMER 2,493,259

THERMOSTATICALLY ACTUATED CONTROL SYSTEM Filed Feb. 22, 1945 2 Sheets-Sheet 2 flyumess: INVENTOR A? I/Vi/l/am 15. f/me/f ATTORNEY Patented Feb. 21, 1950 THERMOSTATICALLY ACTUATED CONTROL SYSTEM William B. Elmer, Lakewood, Ohio, assignor t Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application February 22, 1945, Serial No. 579,230

Claims.

My invention relates to thermostatically controlled devices, and more particularly to thermostatic devices for controlling the operation of mechanisms.

The Government of the United States has been granted a certain royalty-free license for governmental purposes with respect to the invention herein described.

In the electric torpedo that has come into general use during the present war, there are devices, as clock mechanisms, that must be set in operation a given time after the torpedo is fired and still other devices controlled by the clock mechanism that operate in time sequence after the torpedo is under way on its own power. Heretofore hydrostatic means have been in vogue to set a spring wound clock in operation. Such hydrostatic devices are not reliable since any shocks, if of suflicient magnitude, will set the clock in operation. Further, such devices are complicated, expensive and worst of all require a mounting at an opening in thehousing of the torpedo in such manner that the pressure responsive devices within the torpedo are subject to the pressure of the sea water. The environment of my invention is not limited to a torpedo but my invention has general utility, as the objects set forth and the claims presented indicate.

One broad object of my invention is the modification of the invention of mine, disclosed and. claimed in my prior Patent No. 2,284,383, entitled Thermostatic control device, issued May 26, 1942, to make it shockproof and self-locking.

Another broad object of my invention is the provision of shockproof thermostatic control for a mechanism, as a clock relay, or any other mechanism.

A further object is to provide an improved compensating thermostatic motor element that is normally locked against operation in an un operated position until subjected to a given heating eiiect and thereafter locked in its operated position to thus efiect continued control of some mechanism.

A more specific object of my invention is to provide an improved ambient temperature compen sated thermostatic motor element that is locked in a non-operated position during all changes in ambient temperature, is subjected to heating, is unlocked when subjected to a predetermined change in temperature over the ambient temperature because of such heating to thus permit movement of the motor element to an operated position, is locked in its operated position 'once having moved. to such position, and is thereafter no longer subjected to heating.

Other objects and advantages will become more apparent from a study of the following specification and the. accompanying drawings, in which:

Figure 1 is a plan view of my thermostatic structure with most of cover broken away,

Fig. 2 is a front view illustrating structural features of the thermostatic structure shown in Fig. 1,

Fig. 3 is a side view with parts broken away along section line III-J11 of Fig. 1 looking in the direction indicated by the arrows at the end of the section line;

Fig. 4 is a view from the rear of my thermostatic structure showing the structure in the relation it may occupy in the body of a torpedo; and

Fig. 5 is a schematic showing of my thermostatic structure in combination with an electric circuit for heating the thermostatic elements of the structure.

Referring to the figures of the drawings, I designates the base upon which are mounted blocks of insulating material 2 and 3 for rigidly securing the plate-like thermostat 4 to the base I. A cover i9 is disposed above the various elements to be presently described to guard against mechanical injury of the elements. The thermostat 4 is generally in the shape of a rectangular plate and in the manufacture is actually stamped from a single plate of thermostatic metal, the stamping being in such manner that the thermostat has two side or outer strips 5 and 6 of considerably greater width than the strip 1 cut into the shape of a resistance grid. The outer strips 5 and 6 have their rear ends rigidly secured to the insulating blocks 2 and 3, respectively, with the front end or lower end, as seen in Fig. 1, being projected outwardly from the blocks of insulating material in the form of cantilever beams. At the front ends of the strips 5, 5 and l, a relatively rigid strap 8 of insulating material rigidly secures all the strips together so that strips 5, B and I always project from this insulating strap 8 in the same direction.

The rear end of the grid-like strip 1, as shown in Fig. 1, consists of three rearwardly projecting ends rigidly connected together to an insulating block 9 carrying the adjustable screw in for actuating the button I l of the spring wound clock l2. It will be noted that with the construction just described, the thermostatic strips being secured to each other in the manner designated willalways fall in the same cylindrical surface so fi'ring of the torpedo.

long as the temperature to which the respective strips are subjected are not different in magnitude. I, therefore, provide a very efiective thermostatic structure for compensating for changes in ambient temperature because ambient temperature will cause the strips 5, 6 and I to deflect equal amounts so. that all thepointsof the strips will be retained substantially -inthe-=same cylindrical surface. In consequence the insulating block 9 and thus the adjustable bolt It will remain in a fixed position with referencesto-sthe button H regardless of any changes incambient temperature.

A device of the character 'thue-far 'generallyindicated taken by itself is'not shockproofi since any impact from the top or the" bottom w'illtend to deflect the free end of the SI'JI'lDLZ I and thereby may actuate the button I I. To gain a better understanding of the structures hereinafter -"described as forming part of the combination of th-is"-invention,' 'a' brief discussion. of :theuusepto which my device .is to' b'e put-Will fbe. helpful.

The" general use of 'the' electric torpedo requires the operation 'of'certain timing mechanisms'after hydrostatic deviceuin the torpedofat theregion I of a hand-hole -or.similar';opening in :the torpedo so'that adiaphragm'tresponsive to theupressure of the sea water would be exposed to theseazgwatertothus :actuate :a clock; as I 2,::by' depress- I ing..a-':button :as I I.

Such devices I involvesconsiderable mechanical complexity both in their own structure as well --asiiin'thestructure'of the-torpedo and are'notzf shockproof. "To avoid theuse-of the hydrostati- :ca'llyrloperateddevices, I'have modified :my; thermostatic structure, shown, described and claimed rin't myzabove' mentioned patent,-1so that 'it iS'l'bOth shockproofg: assures the continued. operation of.- a 1 mechanism: set in operati'on by. it; andr is. selfdeenergizing once it has been operatedef-rom a contact I being :disposedunder pressureso that a portion th'ereofeabuts therear end. of thelstrip -I :namely abuts -.against the block-lof. insulating materials carrying:theadjustablerbolt II'L .Both

contacts :are secured to the. projection .1 Seat .the

right to'thus project ias. cantilever beam toward the left but above strips Ii-and I; '-.The.deflection "of spring-contact I5 fiS SUmCiBDt-mO close the contacts I4 and. I5.to thusclose one portioncf a circuit-to be hereinafter..discussed.- The left .end;

of contact I 5-has a downwardlyprojectingpor- :tion I5- sondisposed with reference to blocks in "the eventblock 9 is moved -.downwar.dly asuificient .1 distance to actuate the. button I I I it will also .permit the spring I 5 Ito deflect towards the;

front so that the downwardly projectingportion l5ismoves ontopof block 9;..thereby permanently docking the strip Lin .its operated positionito thus thereafter .permanently 1 hold "button I I "down. The :clock It will, therefore, I continue to operate.

oncesetv .in operation.

"To ipreventwdownward deflection :Of the free :end. otthezstrip- I'I except when desired,- ;a hair- ;.=-pin type. of 1a :bim'etallic thermostat I 6 .-is secured son. theuvertlcalsurface 10f: the-clowermeamendzof.

Heretofore, .the' 'hydro- 525 static device 11sed;required the "mounting-"of the the block of insulation 3. The thermostat is thus disposed with its width in a vertical plane. Normally, the left-hand end of the thermostat I6 is disposed under the block of insulation 9 so that any shocks applied to the base from below will not, by virtue of the inertia of the strips't, Bland I andltheiblocks ofsinsulation B and' 9,='-actuate'the button-II. 'The thermostat I6 when subjected to a sufiicient amount of heating will deflect toward the rear or in a clock- .Wise di1'ection,,as seen in Fig. l, with the result that-.it will, once deflected, no longer prevent any vertical movement of the rear end of the *strip :7.

Both thecontact strip I5 as well as the thermostat I6 need'not'necessarily be devised to lock the ..rear end lonlysagainst vertically downward movement as thermostat I6 would do before he- =ing heated, or against vertically upward movement as contact I5 would do once the free end is moveclato itsoperati-ng position. .Thearrange- -ment-may-bensuch as' to prevent-any vertical movements, exceptiwhen desired.v The zshowing made will, however, sufiice for theillustration of the 'tprinciple of operations accomplished by the :contact strip I 5 and the-thermostat I 6;-

To effect the appropriate operationaoi my thermostatic structure in a torpedo,-.I-. providesa source of electrical energy indicated. :by the battery -B connected in series witheartrigger switch I I actuated-to closed .position- [upon firing of: the torpedo. Whenthe-trigger switch is .closed a circuit is established-.from the-battery B' through trigger switch. I I, conductor. I 8,. spring. contacts 'I5 :and I4, the hairpin-[typethermostatlfi, the strips v6, 7 and.:5. in the order-named back to .the .battery B. The.strips---5,-6-..and'l are-merely shown .schematicallycby the single strip I indicated in Fig. 5. Upon:..the .firing.of ,the .torpedo, contacts of thetrigger switchl'l .close whereupon the. circuit .recited ..becomes.,energized and since the .grid portion .of .the thermostaticstructure, namely .strip .1, ,is .of considerablygreater resistance per lunitlength than the strips..5 and. 6, strip I will...become.. unequally. heated. with reference. .to .strips 5land Ii and. inconsequence the free .end, carryingtheblock. .of insulation will be deflected downwardly toaactuatetheclock starting button II.- .I-Iowever such actuation cannot .take place except .whenlthethermostat element .TI 6 Iissufficientlyl deflectedltommoveirom v.under the. block. 9. The-selection. of thermostat I6 is suchsthat but ajew.secondsarerequired, after the electric. current traverses thethermostat IB, .forlitto. deflectlsufiiciently to release block'jIl tor movement in the downward direction. As a matter of fact, the selection is normally so made that the deflection of thermostat'IBprecedes the deflection .of.the.free or.rear end of the strip I, so that there will'be no opportunity for anybinding action betweenthe thermostat I6 and block 9.

The-instantthe'rear orfree end of the strip I has moveda 'sufiicient distance'tdactuate the button II, the spring contact I5 will move over the top of 'theblo'ck of insulation Q-and the downwardly projectingxend15" will prevent any fur ther upward 'moyementmf 'this block, thereby permanently holdinglthezstartingibutton I I in the actuated position;

Atther'same time that" the' contactr I Eamoves to lock-1 the'afreerror :rear 2 end -::of-:.the:strip I its noperated position;;contact I 5: is-zmovediawayirom contact I 4: to: breaknthe nircuit'iheretofore:ttraced withthe.resultxthatmot'zonlynisgthe ploclmmech anism set in operation and maintained in operation but the thermostatic elements are disconnected from the source of electrical energy to prevent any over-heating of these elements.

While I have shown and described but one embodiment of my invention, it is apparent that others particularly after having had the benefit of the teachings of my invention may devise other possibly similar constructions for accomplishing the same result. I therefore, do not wish to be limited to the particular showing herein made, but wish to be limited only by the scope of the claims hereto appended.

I claim as my invention:

1. In a thermostatically actuated control systerm, a thermostatic responsive structure comprising at least two coextending spaced apart flat strips in side by side relation and capable of lying in the same cylindrical surface, means rigidly joining one pair of adjacent ends of the strips to each other, a base, means rigidly securing the other end of one of. the strips to the base, the other end of the second strip, lying adjacent the other end of the first strip, being free to move relative to the base in response to unequal heating of said two spaced apart strips, means mounted on the base and biased against the said other end of the second strip to thus move along and over the cylindrical surface of the said other end of the second strip upon a predetermined movement of the said other end of the second strip with reference to the base to thus retain the otherend of the second strip in the position determined by the predetermined movement, and means actuated by said other end of the second strip by the said predetermined movement thereof.

2. In a thermostatically actuated control system, a thermostatic responsive structure comprising at least two coextending spaced apart flat strips in side by side relation and capable of lying in the same cylindrical surface, means rigidly joining one pair of adjacent ends of the strips to each other, a base, means rigidly securing the other end of one of the strips to the base, the other end of the second strip, lying adjacent the other end of the first strip, being free to move relative to the base in response to unequal heating of said two spaced apart strips, means mounted on the base and biased against the said other end of the second strip to thus move along and over the cylindrical surface of the said other end of the second strip upon a predetermined movement of the said other end of the second strip with reference to the base to thus retain the other end of the second strip in the position determined by the predetermined movement, a thermostatic element disposed to hold the other end of the second strip in its initial position, namely within the cylindrical surface the said other end of the second strip occupies when the strips are not subject to unequal heating, but adapted to release the other end of the second strip when the strips are subject to unequal heating, and means actuated by said other end of the second strip by the said predetermined movement thereof.

3. In a thermostatically actuated control systern, a thermostatic responsive structure comprising at least two coextending spaced apart flat strips in side by side relation and capable of lying in the same cylindrical surface, means rigidly joining one pair of adjacent ends of the strips to each other, a base, means rigidly securing the other end of one of the strips to the base, the other end of the secondstrip, lying adjacent the other end of the first strip, being free to move relative to the base in response to unequal heating of said two spaced apart strips, means for latching the other end of the second strip in a given position upon deflection of the other end of the second strip to said given position, means for retaining the other end of the second strip in its initial position but adapted to release it upon unequal heating of the strips, and means actuated by said other end of the second strip by the said predetermined movement thereof.

4. In a thermostatically actuated control system, a thermostatic responsive structure having coextensive spaced apart portions in side by side relation and capable of lying in the same cylindrical surface,means rigidly joining one pair of adjacent ends of said portions together, a base, means rigidly supporting the other end of one of said portions on the base, means disposed in the path of the other end of the second portion to be operated by movement of said other end of the second portion upon unequal heating, a thermostatic latch fixed on the base and having an element normally engaging the other end of the second portion to hold it in a given position but adapted to release the other end of the second portion upon unequal heating of the portions, and means for locking the other end of the second portion in the position to which it is moved upon unequal heating of the portions.

5. In combination with a mechanism to be set in operation, a thermostatic structure comprising the combination of, a pair of substantially coextensive spaced apart strips of thermostatic material disposed in side by side relation so that the strips lie substantially in the same cylindrical surface and corresponding ends lie adjacent each other, means for rigidly connecting one pair of adjacent ends of the strips together, a base, means for fixing the other end of one of the strips to the base, whereby the other end of the second strip, constituting a free end, is free to move with reference to the base upon subjecting the thermostatic strips to unequal heating, means mounted on the free end to operate said mechanism, and a flat spring at one end rigidly mounted on the base with its loose end disposed with a biasing force against the free end of the second strip, whereby the loose end moves to one side of the cylindrical surface occupied by the free end of the strip upon a predetermined movement of the free end.

6. In combination with a mechanism to be set in operation, a thermostatic structure comprising the combination, of a pair of substantially coextensive spaced apart strips of thermostatic material disposed in side by side relation so that the strips lie substantially in the same cylindrical surface and corresponding ends lie adjacent each other, means for rigidly connecting one pair of adjacent ends of the strips together, a base, means for fixing the other end of one of the strips to the base, whereby the other end of the second strip, constituting a free end, is free to move with reference to the base upon subjecting the thermostatic strips to unequal heating, means mounted on the free end to operate said mechanism, a flat spring at one end rigidly mounted on the base with its loose end disposed with a biasing force against the free end of the second strip, whereby the loose end moves to one side of the cylindrical surface occupied by the free end of the strip upon a predetermined movement of the free end, and a l5 prisingithe combination of; a pair-50f. substantially :ioo'extensiveaspaced apart strips of: thermostatic material disposed in side by side relationso that I t-"t'herstrips: lie"-substantiallyrinrthesamejcylindrical 1:aisurfaceand"corresponding ends lie adjacent-each rs-others means zfOl 'rigidly; :connectiilgronerv pair of .z. .adjacent?ends ofithe stripstogether; aabase means :1 fomfixing thet IOH'IBI? end :of::- one. oft-i the. strips to lithe .eloaseg. whereby it-he other end? of thez second '1, strip; constituting aifreeend; is'freetozmovezwith statics istrips: to .nneiqual; heating, means: moimted noni ltheizfree'rtend to 'operatextsa-id' mechanism, a atsispringi at.=fones-rend'fzrigidly mountedron the f lbasewithrits loose end disposed witha: biasing fiforce. ia'gainsttithe fiteexendxof. I the.-: :sec'ond' strip,

wwherebycthe loose .:end moves to one' :sideof the 'cfcylindrical-i surface? occupied by the .tiree end 2 iof-E-the' istripllrponi a predetermined: moveirient of lither free' end; av third" thermostatic '.strip at: one

end? fixed to i-itheibaseiand" disposed generally in;

the plane of thei-iiat spring and-:cooperativelyen- I? gaging thez'free: lend .of.xthe: second strip to: pre- WXZEHtJ'L'IIlOVEHIGIltS-50f" :the': free- :end of the second esstripsexceptluporr a predetermined: unequal heatning ofithetipain of COEXtGHSiVSiSPZLCBd apart sti'ips stand. electrici means connected in series with said xis'trips to electrically :heatthe strips e 8.lII1 -COI-'l1binatliOI1lWlthi aimechanismxtov =be set 1 in.'-"operation,.=. a..ithermostatic'device comprising ai thermo'static" compositametar plateiha-ving at.

' f frontaiendsvbfs:thesthree strips 's'together, (means 1' =rigidly: connecting :the plurality of rear grid-pormiti'ons 50f lthe'zmiddlenstrip \togethen to provide a 1 .-='-'.sing1e'.rearrfreeeiend-foritheigrid; portion, locking means at the rear free end;?Of?;the:'midd1e' strip l for lookingzthe free rear rend: against movement mar-ten.arpredetermined-rmovement-tof ;the said ifree .:.rear-: end: With treferencertolthe base, lelectric mans 1 finrzuneqiially heating 'thestrips: to cause said prea determinedrmovement of .the said rear .free end, :Fiandsmeans associated with said .reariree end'ior r starting :saidrmechanism.

simcombination with a mechanism ,to be-set .1--,in:;'operation, a": thermostatica device comprising szaithermostatic composite:metalrplate having at lithe :mid..wportion, of the; plate.::. a; .seriesixof slits alternately; extendingito nearsthe-sopposite edges -.;=:oi the plate to f'th'uS definesthree parallel- 1yl disposed lstrips -withnthe" stripg-at-ithe :mid mortion .Jformi ng a ,grid;.of..-re1atively higher: electrical resista-nce..-per..1init -1ength..:thanthe. -tW- out- 5 side-wider.-.strips,- a base --means :for.-'securing r they rear -1 ends 1 of l the Wider -stripsa to the rwbase, meansrrigidly securing the front endsiof -.\the three strips,together,..means rigidlyponnectl .-ing ithe plurality ofrear grid. portions :of .-.the -middle-strip together .toprovide a si-nglerear .Ifree end for ther-grid-portion, locking meansat -.-.the \rear free end of the: middle .strip fonlocking the free rear end against movementafter.apredetermined movementol? the said free-rear: end wwith reference .to.,.the* base, thermostatic means v.for locking-said rear free endagainst movement,

-,. and electric means if or heating said. thermostatic means s to release said :rear; free. .;end.-. and. -for eunequallylheating the strips to. cause said prezlreiaerence'toithe base upon subjectingmheithermo- 1 determined movement of. .thesaid rear .free :end.

10.-...In .combination.. with a. mechanism.\to. be set in--, operation,-. afithermostaticidevice compris- .ing athermostatic .composite; metal plate.having at. the mid portion. of .the plate a-series of. slits 1 alternately, extending .to neanthe. oppositeedges of...the..plate..to.thus define three.paralle1ly...dis-

posed. strips with. the strip,v at. .the mid. portion .fiorming a grid of relatively higher: electrical re- .sistancev per unit length- ,than -the two. outside widerstrips, a. base-.meansLfor securingthe .rear...ends.oi the widenstrips to the. base,.means .rigidlysecuring .the ,front ends of the three strips .togethen, means rigidly .connecting the plurality .of rear. grid-portions. of the middle strip together '.t0.,.prov-ide a single rear ireeend..ior..the ;grid portion, locking means at. the rear free endof .the middle strip for looking the free rear. end against movement after a predetermined move- .ment of-the said iree .rear end with reference to the, base, thermostatic. means for. locking said rear free end against movement, and electric means for. heating saidithermostatic means. to release saidrear free end and for unequally .heatingthe stripsto cause said... predetermined .movement of.the said .rear free end, and means operated by said locking means. to effect, dis- .continuance of any heating of the strips, and "thermostatic .means. after said predetermined movement of'the free rear end.

. WILLIAM. B. ELMER.

REFERENCES CITED The-following references are of record in :the a file of this-patent: 

